Mizuhara Tomoko, Okanoya Kazuo
Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro, Tokyo 153-8902, Japan.
Behav Processes. 2020 May;174:104089. doi: 10.1016/j.beproc.2020.104089. Epub 2020 Feb 24.
Songbirds as vocal learners have been one of the most popular model species to investigate the biological prerequisite to human language. Their songs consist of syllables, which appear as pulse trains in sound spectrograms. When describing the song sequence, researchers consider the syllable to be the unit of the song. Moreover, artificial grammar learning studies asking whether songbirds recognize structural regularities observed in human language often design stimuli using song syllables as components. However, whether syllables are perceptual units is yet to be determined. We found that Bengalese finches, a species of songbird, responded significantly less to one specific syllable when it was temporally placed close to the preceding syllable. The proximity, or silent interval was within the range of what is produced in the natural songs of both Bengalese and zebra finches, and what has been used in other artificial grammar learning studies using zebra finches. Our results suggest the need for a reinterpretation of the description of birdsong structure and of previous artificial grammar learning studies.
作为声乐学习者的鸣禽一直是研究人类语言生物学前提的最受欢迎的模式物种之一。它们的歌声由音节组成，在声谱图中表现为脉冲序列。在描述歌曲序列时，研究人员将音节视为歌曲的单位。此外，关于鸣禽是否能识别在人类语言中观察到的结构规律的人工语法学习研究，通常使用歌曲音节作为组成部分来设计刺激。然而，音节是否是感知单位还有待确定。我们发现，孟加拉雀，一种鸣禽，当一个特定音节在时间上紧邻前一个音节时，对它的反应明显减少。这种接近程度，即静音间隔，在孟加拉雀和斑胸草雀的自然歌声中以及在其他使用斑胸草雀的人工语法学习研究中所使用的范围内。我们的结果表明，需要重新解释鸟鸣结构的描述以及以前的人工语法学习研究。
